<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Document</title>
	<style type="text/css" media="screen">
		body{
			height: 5000px;
		}
		.up{
			width: 50px;
			height: 50px;
			background: #000;
		}
	</style>
	<script type="text/javascript" src="./jquery-1.8.2.min.js"></script>
	<script type="text/javascript" src="./backTop.js"></script>
	<script type="text/javascript">
	$(function(){
		$('.up').backTop();
	})
	
	</script>
</head>
<body>
	<div class="up"></div>
</body>
</html>